Identification_Information:
Citation:
Citation_Information:
Originator: U.S. Dept. of Commerce, Bureau of Census and dataset modifications by Mr. Ed Yockey, USDA Forest Service
Publication_Date: 2000
Title: scounty2m
Geospatial_Data_Presentation_Form: vector digital data
Publication_Information:
Publication_Place: Salt Lake City, UT
Publisher: USDA Forest Service
Other_Citation_Details: file name: scounty2m.shp
Online_Linkage:
Description:
Abstract:
This coverage was identified on the USGS Water Resources NSDI Node site at http://nsdi.usgs.gov. The coverage contains the County boundaries of the continental United States. These boundaries were derived from the Digital Line Graph (DLG) files representing the 1:2,000,000 scale map in the National Atlas of the United States (please see USGS_Procedures_Used in process step description p.4-6).
The data was then modified by USDA Forest Service Personnel for use in the Southern Forest Resource Assessment and exported to a shapefile (please see USDA Forest Service Modifications in process step description p.6).
Purpose: This shapefile is used as a base map for a variety of applications.
Supplemental_Information: The counties included in the coverage are within the following states: AL, AR, FL, GA, KY, LA, MS, NC, OK, SC, TN, TX, and VA.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2000
Currentness_Reference: publication date
Status:
Progress: Complete
Maintenance_and_Update_Frequency: Unknown
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -108.018264
East_Bounding_Coordinate: -74.834524
North_Bounding_Coordinate: 39.952118
South_Bounding_Coordinate: 23.796542
Keywords:
Theme:
Theme_Keyword: counties
Theme_Keyword: boundaries
Theme_Keyword: Administrative and political boundaries
Access_Constraints: None
Use_Constraints: None. The USDA Forest Service does not guarantee the accuracy of this data.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: USDA-Forest Service
Contact_Person: Mr. John M. Pye
Contact_Position: Ecologist
Contact_Address:
Address_Type: mailing and physical address
Address: USDA Forest Service, SRS4851
Address: 3041 E. Cornwallis Rd.
City: Research Triangle Park
State_or_Province: NC
Postal_Code: 27709
Country: USA
Contact_Voice_Telephone: (919).549.4013
Contact_Electronic_Mail_Address: jpye@fs.fed.us
Browse_Graphic:
Data_Set_Credit:
1) USGS- the original county boundary coverage.
2) USDA Forest Service- modifications to data for use in the Southern Forest Resource Assessment (SFRA).
Security_Information:
Security_Classification: Unclassified
Native_Data_Set_Environment: Microsoft Windows 2000 Version 5.0 (Build 2195) Service Pack 3; ESRI ArcCatalog 8.3.0.800
Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report: All counties are accurately labeled.
Logical_Consistency_Report:
Polygon topology is present.
Assessment-standard projection:
Projection: Albers Equal Area
Units: Meters
Spheroid: GRS80
Datum: NAD83
First Standard Parallel: 27 degrees 30 minutes
Second Standard Parallel: 37 degrees 30 minutes
Central Meridian: -90 degrees 00 minutes
Latitude of Origin: 25 degrees 00 minutes
False Easting: 0.0
False Northing: 0.0
Completeness_Report: All polygons have been reviewed for attribution accuracy. A quality control inspection has been performed to eliminate any missing or duplicate labels in the shapefile.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report: All linear delineations are within National Map Accuracy Standards.
Quantitative_Horizontal_Positional_Accuracy_Assessment:
Horizontal_Positional_Accuracy_Value: +/- 1,016 meters
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report: All linear delineations are within National Map Accuracy Standards.
Quantitative_Vertical_Positional_Accuracy_Assessment:
Vertical_Positional_Accuracy_Value: +/- 500 meters
Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator: Mr. K.J. Lanfear, USGS
Publication_Date: 1994
Title: county2m.e00.gz
Publication_Information:
Publication_Place: Reston, Virginia
Publisher: USGS
Other_Citation_Details: file name: county2m.e00.gz
Online_Linkage:
Source_Scale_Denominator: 1:2,000,000
Type_of_Source_Media: Arc Info export coverage
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 1994
Source_Currentness_Reference: publication date
Source_Contribution: USGS 1:2,000,000 Counties coverage
Process_Step:
Process_Description:
This coverage was identified on the USGS Water Resources NSDI Node site at http://nsdi.usgs.gov. The coverage contains the County boundaries of the continental United States. These boundaries were derived from the Digital Line Graph (DLG) files representing the 1:2,000,000 scale map in the National Atlas of the United States (please see below USGS_Procedures_Used referenced from USGS metadata).
USGS_Procedures_Used: This series of maps was published as part of the National Atlas of the United States (USGS, 1970). The maps for the conterminous United States were digitized in 15 sheets and published in the Digital Line Graph (DLG) format as described by Domeratz and others (1983).
Each sheet was prepared by reading the DLG files of the political and water bodies layers, converting them to ARC/INFO, extracting the county boundaries and the coastline, respectively, and joining the two layers together. FIPS codes were assigned to all polygons using available sources, and were checked manually.
Boundaries with adjacent sheets of the 15-sheet set were edgematched manually, arbitrarily choosing one of the sheets as the "correct" border. Edgematching operations adjusted the linework as far as was necessary so that the coverages would fit to a tolerance of 100 meters. The coverage (referred to herein as Version 1.0) was stored as 49 separate coverages (48 states and the District of Columbia) because the ARC/INFO software in use at the time could not process the entire coverage. Individual states could be joined by specifying a tolerance of 100 meters.
From time to time, adjustments were made to the state coverages to reflect changes in U.S. counties. It is believed the accuracy of these adjustments is comparable to the original linework.
For Version 2.0, all state coverages were rejoined and manually edited to produce a perfect edgematch between all states. For states on the original map sheet boundaries, this adjustment averaged less than 20 meters and in no case was more than 100 meters. The whole coverage was CLEANed to a tolerance of 20 meters, which resulted in few, if any, effects on small offshore islands. The coverage also was checked to ensure that it represented current U.S. counties or county equivalents.
The coverage in Version 1.0 stopped at the coastline. There was no attempt to depict offshore areas. The created some problems when the coverage was used to assign county codes to sampling stations located near the coast. To help in this matter, Version 2.o includes offshore extensions of the county polygons. The (water) boundaries of many of these polygons are arbitrary.
The Canadian Great Lakes features are another new addition to Version 2.0. They were added to improve the utility of the coverage for visual displays. Although the Canadian Great Lakes are logically represented by a single polygon, practical considerations -- the inability of some software to plot polygons with a large number of vertices -- made it necessary to separate them into 4 polygons. The dividing lines are located in narrow channels to minimize interference with plotting patterns. Canadian islands within the Great Lakes also were included.
All tics were relocated to places that are easily visible on maps of the United States, to help in registering maps that may not otherwise have adequate registration information.
To expedite accessing parts of the coverage, certain items have been indexed with the procedure, index_county.aml. See Section 3. A spatial index also was created.
When using this coverage to clip or intersect other coverages, a tolerance as low as 2 meters can be used.
The processing used to derive this coverage moved boundaries from their positions on the original maps. In cases of conflicting lines, preference was given to forming the correct topology. Strictly speaking, this coverage is not identical to the source materials. These changes were unavoidable in producing a continuous coverage of the conterminous United States.
For revision 2.1, it was necessary to alter about 100 arcs. This was accomplished with ARCEDIT using the 1:100,000 TIGER county coverage as a background. These arcs were matched to the background so that they matched at least as close as other arcs that were not edited.
Related Spatial and Tabular Data Sets: This coverage is part of series of 1:2,000,000-scale basemaps covering the United States. Layers presently available in this set include:
county2m -- County and state boundaries.
waterbod2m -- Water Bodies.
huc2m -- Hydrologic cataloging units (basins).
For Version 2.3.1, USGS corrected the following 2 errors found in version 2.3. First, a duplicate label in the water polygon for Hampton, VA, FIPS 51650 was removed. Second, the PLYTYPE attribute was corrected to PLYTYPE=9 for the external polygon. Because this had been set to 0 in some prior processing, the BNDTYPE values for outside arcs were not correct. Ran index_county.aml to correct the BNDTYPE values.
Other References Cited: Domaratz, M. A., Hallam, C. A., Schmidt, W. E., and Calkins, H. W., 1983. USGS Digital Cartographic Data Standards: Digital Line Graphs from 1:2,000,000-scale Maps. U.S. Geological Survey Circular 895-D, 38p.
U. S. Geological Survey, 1970. National atlas of the United States of America: Washington D.C., U. S. Geological Survey, 417p.
USDA Forest Service Modifications:
Sept. & Oct.-2000:
The coverages were downloaded by USDA Forest Service personnel on 22-Sep-2000 in compressed Arc Info Export format along with their associated metadata. The coverages were then reprojected to match Assessment standard Albers using the Arc Info PROJECT command, subsetted to the thirteen Southern states of the Assessment using Arc View's Theme Query tool and state FIPS code, then exported as shapefiles.
14-NOV-2000:
In early November 2000 two problems were discovered with the two county coverages:
1. slivers were found associated with Virginia county boundaries, these were manually edited and removed
2. multiple records per county or municipality interfered with join operations and subsequent analyses, these were similarly identified and removed.
Both operations were performed on the Albers-projected shapefiles and renamed as scty100 and scty2m. These have replaced the USGS county coverages on the Assessment web site.
Process_Date: 14-Nov-2000
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: USDA-Forest Service
Contact_Person: Mr. Edwin Yockey
Contact_Position: GIS Specialist
Contact_Address:
Address_Type: mailing address
Address: PO Box 2680
City: Asheville
State_or_Province: NC
Postal_Code: 28801
Country: USA
Contact_Voice_Telephone: (828).257.4857
Contact_Facsimile_Telephone: (828).257.4856
Contact_Electronic_Mail_Address: eyockey@fs.fed.us
Process_Step:
Process_Description: Metadata imported.
Source_Used_Citation_Abbreviation: L:\forest\sfra\download_data\county_bound\albers\scty100\scounty100.xml
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Vector
Point_and_Vector_Object_Information:
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: G-polygon
Point_and_Vector_Object_Count: 1342
Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Map_Projection:
Map_Projection_Name: Albers Conical Equal Area
Albers_Conical_Equal_Area:
Standard_Parallel: 27.500000
Standard_Parallel: 37.500000
Longitude_of_Central_Meridian: -90.000000
Latitude_of_Projection_Origin: 25.000000
False_Easting: 0.000000
False_Northing: 0.000000
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: coordinate pair
Coordinate_Representation:
Abscissa_Resolution: 0.004096
Ordinate_Resolution: 0.004096
Planar_Distance_Units: meters
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1983
Ellipsoid_Name: Geodetic Reference System 80
Semi-major_Axis: 6378137.000000
Denominator_of_Flattening_Ratio: 298.257222
Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: scounty2m
Attribute:
Attribute_Label: FID
Attribute_Definition: Internal feature number
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Unrepresentable_Domain: Sequential unique whole numbers that are automatically generated.
Attribute:
Attribute_Label: Shape
Attribute_Definition: Feature geometry
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Unrepresentable_Domain: Coordinates defining the features.
Attribute:
Attribute_Label: AREA
Attribute_Definition: The size of the shape in shapefile units
Attribute_Definition_Source: ESRI
Attribute:
Attribute_Label: PERIMETER
Attribute_Definition: The perimeter of the shape in shapefile units
Attribute_Definition_Source: ESRI
Attribute:
Attribute_Label: COUNTY2M_
Attribute:
Attribute_Label: COUNTY2M_I
Attribute:
Attribute_Label: FIPS
Attribute_Definition: User attributed state and county FIPS zone
Attribute_Definition_Source: US Geological Survey
Attribute:
Attribute_Label: ST
Attribute_Definition: User attributed two letter abbreviations for the state (i.e. TX)
Attribute_Definition_Source: US Geological Survey
Attribute:
Attribute_Label: CNTYNAME
Attribute_Definition: User attributed county name
Attribute_Definition_Source: US Geological Survey
Attribute:
Attribute_Label: PLYTYPE
Attribute_Definition: User defined attribute (i.e. 0 is US Land)
Attribute_Definition_Source: US Geological Survey
Attribute:
Attribute_Label: WORKB
Attribute:
Attribute_Label: FIPSST
Attribute_Definition: User attributed state FIPS zone
Attribute_Definition_Source: US Geological Survey
Attribute:
Attribute_Label: FIPSCNTY
Attribute_Definition: User attributed county FIPS zone
Attribute_Definition_Source: US Geological Survey
Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: USDA-Forest Service
Contact_Person: Mr. John Pye
Contact_Position: Ecologist
Contact_Address:
Address_Type: mailing and physical address
Address: USDA Forest Service, SRS4851
Address: 3041 E. Cornwallis Rd.
City: Research Triangle Park
State_or_Province: NC
Postal_Code: 27709
Country: USA
Contact_Voice_Telephone: (919).549.4013
Contact_Electronic_Mail_Address: jpye@fs.fed.us
Resource_Description: Downloadable Data
Distribution_Liability:
Data Content and Use Disclaimer
The USDA Forest Service, Southern Forest Resource Assessment or SFRA, provides data to users of digital geographic data. The USDA Forest Service is in no way condoning or endorsing the application of these data for any given purpose. It is the sole responsibility of the user to determine whether or not the data is suitable for the intended purpose. It is also the obligation of the user to apply the data in an appropriate and conscientious manner. The USDA Forest Service provides no warranty, nor accepts any liability occurring from any incomplete, incorrect, or misleading data, or from any incorrect, incomplete, or misleading use of the data. Much of the USDA Forest Service data is based on and maintained with Arc Info and Arc View Software developed by the Environmental Systems Research Institute (ESRI). In addition, much of the information presented uses conventions and terms popularized by Arc Info and Arc View and their user community. USDA Forest Service in no way represents the interests of ESRI nor acts as an agent for them.
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: .shp
Format_Version_Number: Arc View Shapefile
Format_Specification: Arc View
Format_Information_Content: Counties within the continental United States
File_Decompression_Technique: zip file
Transfer_Size: 2.562
Metadata_Reference_Information:
Metadata_Date: 20041118
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: USDA-Forest Service
Contact_Person: Mr. John Pye
Contact_Position: Ecologist
Contact_Address:
Address_Type: mailing and physical address
Address: USDA Forest Service, SRS4851
Address: 3041 E. Cornwallis Rd.
City: Research Triangle Park
State_or_Province: NC
Postal_Code: 27709
Country: USA
Contact_Voice_Telephone: (919).549.4013
Contact_Electronic_Mail_Address: jpye@fs.fed.us
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time
Metadata_Access_Constraints: None
Metadata_Use_Constraints: None
Metadata_Security_Information:
Metadata_Security_Classification: Unclassified
Metadata_Extensions:
Online_Linkage: http://www.srs.fs.usda.gov/econ
Metadata_Extensions:
Online_Linkage: http://www.esri.com/metadata/esriprof80.html
Profile_Name: ESRI Metadata Profile